Effects of Aerobic Exercise on Physical Fitness in Obesity Using Fox vs. Tanaka's Maximum Heart Rate and Percentage vs. Karvonen Methods.

Abstract

The intensity of aerobic exercise is influenced by maximum heart rate (MHR), which can be assessed through an incremental exercise test. However, this method requires specialized equipment and a level of fitness that individuals who are sedentary or overweight may lack. Therefore, estimating MHR using formulas is essential. Various methods exist to calculate MHR, but their effectiveness in real exercise programs for obese individuals remains unclear. This study aimed to investigate the effects of aerobic exercise using different intensity calculation methods, specifically comparing Fox's and Tanaka's maximum heart rate (MHR) equations, as well as the Percentage and Karvonen methods for target heart rate (THR). Seventy-eight men aged 20 to 30 with a body fat percentage of over 20% were divided into one control group and four aerobic exercise groups. EG1 and EG3 used Fox's and Tanaka's equations for MHR and THR from the percentage, while EG2 and EG4 applied the Karvonen method for THR. Participants engaged in 45 minutes of moderate-intensity walking or running on a treadmill four days a week for 12 weeks. Body weight, body fat percentage, BMI, resting heart rate (RHR), and VO₂ max were measured at baseline and after the intervention. After 12 weeks, all exercise groups demonstrated significant improvements in VO₂ max, as well as reductions in body weight, body fat percentage, BMI, and resting heart rate (RHR), whereas the control group showed no changes. No significant differences were found among the exercise groups. Aerobic exercise at various intensities effectively enhances cardiovascular fitness and body composition in obese individuals, indicating that these methods are equally beneficial.